Why do we not use probes in this dna paternity simulation and still obtain results?

In DNA paternity test, we do not use probes for it cannot confirm the identity of an individual. Instead, it technically rule out a parent in DNA paternity test and this is the reason why we can still obtain results. 

A probe is a small piece of DNA that is a match for a specific part of a single strand of DNA since everyone’s DNA is different. This strand is cut into different number of fragments and different lengths. In paternity test, the length of these fragments are match with the child.

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the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.